Disable Travis notification emails.

This doesn't work as well as I hoped, and tends to have forks spamming us.
Wait for ct-server to exit.
Character set checking for few of ASN.1 strings.
Reduce DNS test noise (fixes #242).
Added entries queue size limit.
Add tools to dump logged certificates and STHs.

They are rather basic for now, but are useful when debugging servers using
the FileDB storage.
Basic logging of issues in certificates.
Applied most of design comments.
Modified highlights, finished checking of dnsnames

Removed leftovers from previous of highlights.
Changed Highlight to Observation, seperated checks
Removed 'return []' in favor of check(cert) or [].
Removed leftover highlight.
Changed equality operator of observations.
Monitor report test.
Algorithm test.